The present invention relates to a preassembled operating panel for vehicle doors.
Vehicle doors are known to comprise an inner and outer metal sheet clinched and welded together to form a frame, the top portion of which defines a window frame fitted with a window sliding between the two sheets, and the bottom portion of which defines the frame of a box-section body comprising an inner and outer panel integral with the bottom frame. The outer panel forms the bottom portion of the outer sheet, and defines the outer shape of the door, while the inner panel forms the bottom portion of the inner sheet, and presents a number of openings through which to fit the working parts of the door (lock, window regulator, etc.) inside the gap on the box-section body. Once the working parts are assembled, the inner panel is fitted with a finish panel normally made of synthetic material and the inner surface of which normally incorporates finish components such as armrests, handles, etc.
In recent times, mainly for the purpose of speeding up on-line assembly and subsequent testing and setup, doors have been devised wherein the inner panel, formerly an integral part of the door structure, is replaced by a preassembled operating panel assembled by means of screws or similar removable fasteners, and fitted with the lock and window regulating and guide devices.
The load-bearing structure of the bottom portion of doors of the aforementioned type is thus reduced to an outer sheet, and an inner sheet clinched and welded peripherally to the outer sheet and having an opening extending over substantially the entire bottom portion of the door. On such doors, the opening formed in the inner sheet is partially closed by the operating panel connected to the inner sheet, while the inside of the door is defined as before by the finish panel.
Though widely used, known doors of the aforementioned type present several drawbacks both technically and economically. In particular, removal of substantially the entire bottom portion of the inner sheet for assembling the operating panel drastically reduces the torsional resistance of the load-bearing structure of the door, so that automated assembly and welding of the door involve the use of high-cost automatic handling solutions.